In filling machines used in the brewing and dairy industries, the requirements on high filling capacity, precise filling accuracy, acceptable washing and sterilization capability and overall economy are of decisive importance. Filling machines for, for instance, bottles often fill a large number of bottles simultaneously, in which event each bottle is advanced by means of a conveyor to a filling station beneath a filler pipe through which a metered quantity of the desired contents is fed. Each filler pipe is, therefore, connected to a holding tank for the intended contents via a metering or dispensing device, e.g., a piston pump which, in each working stroke, measures and transfers the desired volume of contents from the holding tank to the bottle. In the event of contents of low viscosity, e.g., freely running liquids such as milk and juice, it is possible, instead of the relatively expensive and complex piston pump, to provide each filler pipe with a flowmeter and a valve controlled by the flowmeter, the valve opening when the bottle has been placed in the correct filling position beneath the filler pipe and closing when the flowmeter has measured the passage of the desired volume of contents.
Both of the above-outlined design and construction principles are generally employed and have proved to satisfy adequately the established requirements on efficiency, accuracy and washing capability. However, the costs involved (in particular in large scale filling plants) are relatively high since each filler pipe must be fitted with its own piston pump or flowmeter. Since large-scale filling plants featuring 8, 16 or 32 filler pipes are not uncommon, the capital investment costs will be considerable. In addition, the large number of piston pumps or flowmeters requires meticulous individual adjustment and control, which also correspondingly increases running costs.